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`modules.moment().diff()` throws "TypeError: Cannot read property 'isValid' of undefined"
4 CommentsSorted by Oldest First
Hi @brandly, I just wanted to let you know we're taking a look at this- our BL expert is out of pocket at the moment but we'll revert asap.
"Diff" is expecting a parameter to use to compare against. It can be another moment or string that matches a date. For example, to compare the start and stop time of some code:
`
var start = moment();
// ... do some work
var diff = moment().diff(start);
`
Another example, to get the difference between a specified date and the current moment:
`
var pointInTime = '2014-05-01T00:34:06+00:00';
var currentMoment = moment();
var diff = currentMoment.diff(pointInTime);
`
`
var start = moment();
// ... do some work
var diff = moment().diff(start);
`
Another example, to get the difference between a specified date and the current moment:
`
var pointInTime = '2014-05-01T00:34:06+00:00';
var currentMoment = moment();
var diff = currentMoment.diff(pointInTime);
`
What version of moment.js is being exposed? Previously, running on Kinvey, the code I posted above worked as expected. And currently, in the console on momentjs.com, I can call `diff` without any arguments on an instance of `moment`, and it will return the difference between the current time and that moment.
http://i.imgur.com/Kqmmglz.jpg
http://i.imgur.com/Kqmmglz.jpg
It does appear to be a platform bug. I will tag it to be fixed in our next release of business logic.
brandly
```
{"error":"BLRuntimeError","description":"The Business Logic script has a runtime error. See debug message for details.","debug":"TypeError: Cannot read property 'isValid' of undefined"}
```
After investigating, it appears to calling `modules.moment().diff()` is the source of the problem. In our actual use case, we're passing an ISO date string into moment. Something like:
```
var iso = moment().toISOString();
moment(iso).diff();
```
Testing this out on moment.js works as expected. However, in Kinvey, it breaks even without passing an ISO string, so there doesn't seem to be any user-caused error.